Re: [PATCH 2/3] x86/mce: Fix incorrect "Machine check from unknown source" message

From: Borislav Petkov
Date: Tue May 29 2018 - 06:43:14 EST


On Fri, May 25, 2018 at 02:41:55PM -0700, Tony Luck wrote:
> @@ -1287,12 +1292,17 @@ void do_machine_check(struct pt_regs *regs, long error_code)
> no_way_out = worst >= MCE_PANIC_SEVERITY;
> } else {
> /*
> - * Local MCE skipped calling mce_reign()
> - * If we found a fatal error, we need to panic here.
> + * If there was a fatal machine check we should have
> + * already called mce_panic earlier in this function.
> + * Since we re-read the banks, we might have found
> + * something new. Check again to see if we found a
> + * fatal error. We call "mce_severity()" again to
> + * make sure we have the right "msg".
> */
> - if (worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3)
> - mce_panic("Machine check from unknown source",
> - NULL, NULL);
> + if (worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3) {
> + severity = mce_severity(&m, cfg->tolerant, &msg, true);

Looking at this more while cleaning the whole thing up, that severity
doesn't get read anywhere past this line, AFAICT...

--
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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